Electrophotographic printing is a well known and commonly used method of copying or printing original documents. Electrophotographic printing is performed by exposing a light image representation of a desired document onto a substantially uniformly charged photoreceptor. In response to that light image the photoreceptor discharges, creating an electrostatic latent image of the desired document on the photoreceptor's surface. Toner particles are then deposited onto the latent image to form a toner image. That toner image is then transferred from the photoreceptor onto a receiving substrate such as a sheet of paper. The transferred toner image is then fused to the receiving substrate. The surface of the photoreceptor is then cleaned of residual developing material and recharged in preparation for the production of another image.
Many electrophotographic printers use flexible belts. For example, exposure is often performed on flexible belt photoreceptors, transfer often involves the use of flexible transfer belts, and fusing is often performed using flexible fusing belts. Flexible belts are of two types, seamed or seamless. Seamed belts are fabricated by fastening two ends of a web material together, such as by sewing, wiring, stapling, or gluing. Seamless belts are typically manufactured using relatively complex processes that produce a continuous, endless layer. In general, seamless belts are usually much more expensive (5-7X) than comparable seamed belts. While seamed belts are relatively low in cost, the seam introduces a "bump" that can interfere with the electrical and mechanical operations of the belt. For example, if a seamed belt is a photoreceptor the seam can interfere with the exposure and toner deposition processes, resulting in a degraded final image. While it is possible to synchronize the printer's operation such that the seam area is not exposed, such synchronization adds to the printer's expense and complexity. Additionally, even with synchronization the mechanical problems related to the seam bump, such as excessive cleaner brush wear and mechanical vibrations, still exist. Therefore low cost seamless belts have significant advantages over seamed belts.
Electrophotographic printing belts, whether seamless or seamed, are usually comprised of multiple layers, with each layer introducing a useful property. For example, one layer might provide the majority of a belt's mechanical strength, another might introduce an imaging layer, and another might improve a belt's toner release properties, while yet another might improve thermal properties. Because multiple layers should be mutually compatible, and since such compatibility significantly limits that range of acceptable materials, manufacturing multiple layer electrophotographic printing belts is particularly challenging.
Therefore, given the difficulty of manufacturing seamless flexible belts and of manufacturing multiple layer flexible belts, new manufacturing processes for such flexible belts would be beneficial.